The culture of hematopoietic cells for cell and gene therapies is a rapidly growing area within the field of applied hematology and tissue engineering. As evidenced by recent clinical trials (1 ), ex vivo expanded hematopoietic cells offer great promise for the reconstitution of in vivo hematopoiesis in immunocompromised patients who have undergone chemotherapy. Other potential applications for ex vivo expansion include production of cycling stem and progenitor cells for gene therapy, expansion of dendritic cells for immunotherapy, and production of red blood cells (RBCs) and platelets for transfusions (2 ).
